Improved drill-chuck



oz me Y Witnesses:

im. POIOTO UTHOGRAPHER WASHINGTON n. C

ELI H. BABOGKQOF CANANDAIGUA, N'EW YORK.

Letters Patent No. 78,916, dated June 16, l1858.

IMPROVED DRILL-CHUCK.

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TO ALL WIIOM IT MAY CONOERN:

Be it known that LIELI Hi BnBCOCK, of Canandaigua, in the county of Ontario, and State of New York, have invented a new and improvedDrill-Chuck; andI do hereby-declare that the followiugis a full, clear, exact description thereof, which will enable those skilled in the art to make and use the same, had to theaccompanying drawings, forming part 0E this specification. i

` This invention relates to an improvement iul the method of holding and truing steel drills in lathes and drilling-machines, whereby machine-work is greatly facilitated, and whereby the process of drilling in iron, steel, or other metals can he muchmorceccurately performed than when done by' drills held inthe ordinary ll'laillnel. l i

And the invention cousistsin securing the drill in au elastic conicaljaw, with a screwthread thereon, and a conical nut which Vengages therewith, and also in an elastic reducer, whereby drillsof smaller size: may be firmly and accurately centred and held while in use, as will be hereinafter more fully described.

Figure is a longitudinal'sectional view of the` chuck and drill, with the reducer in the chuck, the section boing through the line :uw of iig. 2.

Figure 2 is a cross-section of the chuck with the nut of?.

Figure 3 shows the outer end oi' the reducer, as seen from the line y Figure 4 is a view of a drill prepared forthe chuck.`

Similar letters oi' reference indicato corresponding parts.

A represents the chuck, which is slit from its outer end to naar the base of the cone, 'rendering thereby the outer end compressible or elastic, so that it is made to firmly cmbraecthe shank ot' the drill, or the reducer, upon application of thc nut.A l

l B is the nut, whichis made conical within'to t the chuck, as seen in the drawing.

C is the reducer, which is made to fit the chuck the same as the shank ot' the larger drill, and it also is slit so that its sides and outer end are elastic or compressible `for embracing the shank of the smaller drill, upon the and reference being v application of the nut B.

represents the slits in the chuck B, and e the slits in the reducer C.

There may be more o'r lcss of these slits in either the'chuck or reducer.

It will be seen that as the chuck, reducer, and drills are fitted to a common centre, the application or effect ot the conical nut will bc to truc the drills accurately to that centre, and to hold them there while being used.

The nut is readily removed or screwed on by means of a wrench,

When unscrewcd or loosened, the elastic sides of the chuck or reducer will allow the drill to be easily removed By this method of fastening, the drills VVwill always'hetrue to the centre, and ready for use, while the operator will be enabled to perform his work in a much more perfect and` workmanlike manner than he could with drills secured to the mandrel iu the ordinary manner.

Having thus described my invent-ion, I claim as new, and desire to secure by Letters Patent- In combination with the chuck A, the nut B and the reducer C, substantially as and-for the purpose described.

E Lr n. Bassoon.

Witnesses:

JOHN S. McOLUun, JOHN STANDISH. 

